Process and machine for making batches of sheets from a top of a pile

Abstract

A machine for creating a batch of blanks out of a pile of blanks and for removing the batch of blanks from the pile consists of a fixed stop positioned along one surface of the blanks, a jogging device disposed opposite the fixed stop, a movable stop positioned in a line with the fixed stop, a separating device arranged adjacent the fixed stop for engaging an upper surface of the pile to raise the pile to create a free space, a conveyor insert movable from a position outside of the pile into the free space for transferring the blanks raised by the separator out of the pile as a batch of blanks.

We claim: 
     
       1. In a machine having a pile elevator, a fixed front stop adjacent the pile elevator, a separator for engaging a portion of a pile of sheets on the elevator, and a conveying system for removing a batch consisting of an upper portion of the pile separated from the pile by the separator, the improvements comprising the separator being mounted in the machine adjacent the fixed front stop for engaging a first surface of the pile and creating a free space between a raised batch of sheets and a remaining portion of the pile, a jogger being positioned for acting on a rear surface of the pile opposite the first surface, and the conveying system being positioned adjacent the separator and having an end shiftable between a first position clear of the pile and a second position partially inserted in the free space between the raised batch and the remaining portion of the pile. 
     
     
       2. In a machine according to claim 1, wherein the conveying system includes a fixed first part and a second part shiftable relative to the first part in order to be able to penetrate into the free space. 
     
     
       3. In a machine according to claim 2, wherein the second part comprises a first support shiftable relative to the first part and a second support having a shape of a finger tiltable around a horizontal axis relative to the first support. 
     
     
       4. In a machine according to claim 3, wherein the conveying system consists of at least one belt being guided by a plurality of pulleys mounted on said first and second parts to form a closed circuit, one of said pulleys being arranged to compensate for the variations in spacing between the pulleys on both first and second parts during shifting of the second part relative to said first part. 
     
     
       5. In a machine according to claim 4, wherein a return pulley is situated adjacent a free end of the finger, which free end is provided with a tapering portion for insertion into the free space. 
     
     
       6. In a machine according to claim 1, wherein the separator includes a member having a first tooth adapted to engage a lowermost sheet of the batch, said member being mounted in a main frame which is pivotably mounted in said machine and and said member being movable toward said pile to form an angle of approximately 12° relative to the first surface of the pile as the tooth of the member engages a leading edge of the sheets. 
     
     
       7. In a machine according to claim 6, wherein said member includes a contact surface provided with auxiliary teeth situated above the first tooth. 
     
     
       8. In a machine according to claim 6, wherein the separator includes an auxiliary support mounted for essentially vertical on movement on said frame and being shiftable with said main frame until the first tooth engages a surface of the pile. 
     
     
       9. In a machine according to claim 1, wherein the separator includes a member having teeth for engaging edges of the pile to determine a lowermost sheet of the batch, said member being mounted in a frame for vertical movement to raise the batch from the pile, said separator including a finger-shaped pin with a tip, said pin being shiftable between a first position in which the tip is withdrawn from the pile to a second position with the tip extending into the free space created by the teeth of the member lifting the batch from the pile. 
     
     
       10. In a machine according to claim 9, wherein said member is supported on an auxiliary support and the pin is tiltable around an axis mounted on the auxiliary support. 
     
     
       11. In a machine according to claim 10, wherein the member is mounted for tiltable movement around an axle on said auxiliary support to enable parallelism of a surface of the member to the front stop. 
     
     
       12. In a machine according to claim 11, wherein the separator is tiltable between a first fixed position with the member being parallel to the front stop, which position is determined by contact of the separator member with said auxiliary support and a second variable position determined by a spring acting between an upper portion of the member and the auxiliary support. 
     
     
       13. In a machine according to claim 1, which includes pressure means acting on the top of the batch to hold the batch on the conveying system as the batch is shifted off of the pile, said pressure means being shiftable from a position engaging an uppermost sheet of the batch to a position withdrawn from the uppermost sheet. 
     
     
       14. In a machine according to claim 1, wherein the fixed front stop is slanted at an angle of about 7° with respect to a vertical plane, said fixed front stop having a movable upper portion shifted between a first position in which the upper portion engages the first surface of the pile and a second position in which the upper portion enables the forward shift of the batch off of said pile. 
     
     
       15. In a machine according to claim 14, wherein the upper portion of the front stop is mounted for rotation between the first and second positions on an axle mounted on a front of the front stop. 
     
     
       16. In a machine according to claim 1, wherein said jogger includes a rectangular plate mounted on a first carriage, said first carriage being mounted on a second horizontal carriage being shiftable to cause jogging of the pile, said second horizontal carriage being shiftable in a frame by means of a drive worm and motor to compensate for different size piles. 
     
     
       17. A process for creating a batch of a plurality of workpieces from a top of a pile of workpieces and for transferring the batch in a transfer direction extending perpendicularly to a first surface of the pile to a machine for processing the batch, said process including holding the pile on the first surface, jogging a rear surface of the pile in an upper portion of the pile, engaging an edge of a workpiece lying on the first surface of the pile in an upper part of the pile to create an engaged workpiece which is on the bottom of a batch with the number of workpieces in the batch being determined by the number of workpieces resting on the engaged workpiece, raising the engaged workpiece to create a free space between a lowermost workpiece of a raised batch and an uppermost workpiece of a remaining pile of workpieces, inserting an end of a conveying device into the free space, then releasing the engaged workpiece and operating the conveying device to transfer the batch in the transfer direction.